In recent years, in a store such as a large retail store or a convenience store, there is a self-checkout sales data processing apparatus with which a customer carries out a sales registration operation and a settlement operation by himself or herself.
The self-checkout sales data processing apparatus, e.g., self-checkout POS terminal (self POS), is convenient in a case in which a small quantity of commodities are purchased, because the transaction time of the commodities can be reduced with the use of the self-checkout sales data processing apparatus.
However, there is a case in which customers who are not used to the self-checkout sales data processing apparatus, or old people and children who are unfamiliar with the operation hesitate on the way of the operation or make a miss operation on the self-checkout sales data processing apparatus. In this case, the customer has to call an attendant who manages the self-checkout sales data processing apparatus to deal with it; instead, much time is taken.